This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Fund for the time periods indicatedregardless of whether or not you redeem your shares at the end of such periods. The example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same as those shown in the table. The one year amounts shown reflect the applicable expense reimbursements and waivers noted in the expense table. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy Narrative [Text Block]

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GMO seeks to achieve the Fund’s investment objective by investing the Fund’s assets in the sectors within the fixed income market that GMO believes offer the most attractive risk-adjusted returns. GMO utilizes an investment process that incorporates a top-down and bottom-up research-driven framework that relies on both fundamental and quantitative techniques designed to take advantage of relative value opportunities within the fixed income markets. The Fund is a fund of funds and invests primarily in other funds managed by GMO whether now existing or created in the future (“underlying GMO Funds”), including GMO MAC Implementation Fund, GMO Emerging Country Debt Fund, GMO High Yield Fund, GMO Opportunistic Income Fund and GMO Systematic Investment Grade Credit ETF. In deciding how to allocate Fund assets across fixed income sectors, GMO uses various techniques to evaluate the relative attractiveness of particular markets utilizing a variety of inputs. GMO uses its quantitative forecasts of fixed income asset class returns as well as its proprietary risk modeling for corporate defaults, credit risk and interest rates as part of its top-down investment process. GMO also may consider the relative attractiveness of yield curve and duration positions across sectors of the fixed income market. In addition, GMO seeks to identify opportunities arising from unusual market conditions not otherwise identified by its quantitative models and uses various portfolio construction techniques to manage risk. The models and techniques used by GMO take into account value criteria, quality factors (including ESG (environmental, social, and governance) criteria in some cases), momentum, and liquidity. The Fund may invest in any sector of the bond market and is not required to maintain a minimum or maximum allocation of investments in any one sector. The Fund may invest in bonds of any maturity, duration, and credit quality. GMO changes the Fund’s holdings of particular asset classes in response to changes in GMO’s investment outlook and its assessment of market valuations and may use redemptions or purchases of Fund shares to rebalance the Fund’s investments. The factors GMO considers and investment methods GMO uses can change over time. In pursuing its investment program, the Fund may invest in bonds denominated in various currencies, including non-U.S. and U.S. government bonds, agency bonds, leveraged loans and corporate bonds, asset-backed securities, emerging country sovereign and quasi-sovereign debt securities, investment grade bonds, below investment grade bonds (commonly referred to as “high yield” or “junk bonds,”), and inflation-indexed bonds. The Fund also may invest in exchange-traded funds (ETFs) and exchange-traded and over-the-counter (OTC) derivatives, including futures contracts, currency options, forward currency contracts, repurchase agreements and reverse repurchase agreements, swap contracts (such as credit default swaps, swaps on securities and securities indices, total return swaps, interest rate swaps, currency swaps, cross currency basis swaps, commodity swaps, inflation swaps, municipal swaps, and other types of swaps), interest rate options, and other types of derivatives. In addition, the Fund may lend its portfolio securities. The Fund is not limited in its use of derivatives or in the total notional value of its derivative exposure. Leverage is not a principal component of the Fund’s investment strategy. However, because of its derivative positions, the Fund may at times have gross investment exposure in excess of its net assets (i.e., the Fund may be leveraged) and, therefore may be subject to higher risk of loss during those times than if the Fund were not leveraged. The Fund’s performance can depend substantially on the performance of assets or indices underlying its derivatives even though it does not own those assets or indices. GMO does not seek to maintain a specified interest rate duration for the Fund, and the Fund’s interest rate duration will change depending on the Fund’s investments and GMO’s assessment of different sectors of the bond market. The Fund’s interest rate duration may be positive or negative. The Fund may invest in securities of companies of any market capitalization. Under normal circumstances, the Fund invests directly or indirectly (e.g., through underlying GMO Funds) at least 80% of its assets in credit-related investments (see “Name Policies”). The term “credit-related investments” includes (i) obligations of an issuer to make payments on future dates of principal, interest (whether fixed or variable) or both and (ii) synthetic debt instruments created by GMO by investing in derivatives (e.g., a futures contract, swap contract, currency forward, or option). In seeking to achieve the Fund’s investment objective, GMO may invest a significant portion of the Fund’s net assets in cash and cash equivalents. The Fund may also invest in GMO U.S. Treasury Fund, in money market funds unaffiliated with GMO, and directly in the types of investments typically held by money market funds.

Bar Chart and Performance Table [Heading]

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Performance

Performance One Year or Less [Text]

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Because the Fund had not yet completed a full calendar year of operations as of the date of this Prospectus, performance information for the Fund is not included.

Risk Return Abstract

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Risk [Text Block]

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●Credit Risk – The Fund runs the risk that the issuer or guarantor of a fixed income investment (including a sovereign or quasi-sovereign debt issuer) or the obligor of an obligation underlying an asset-backed security will be unable or unwilling to satisfy its obligation to pay principal and interest or otherwise to honor its obligations in a timely manner or at all. The market price of a fixed income investment will normally decline as a result of the failure of an issuer, guarantor, or obligor to meet its payment obligations or in anticipation of such a failure. Below investment grade investments have speculative characteristics, and negative changes in economic conditions or other circumstances are more likely to impair the ability of issuers of those investments to make principal and interest payments than issuers of investment grade investments. In addition, investments in emerging country sovereign or quasi-sovereign debt are subject to a heightened risk that the issuer responsible for repayment of the debt may be unable or unwilling to pay interest and repay principal when due, and the Fund may lack recourse against the issuer in the event of a default. Investments in quasi-sovereign debt also are subject to the risk that the issuer will default independently of its sovereign. Investments in distressed or defaulted or other low quality debt investments generally are considered speculative and are subject to substantial risks not normally associated with investments in higher quality securities, including adverse business, financial or economic conditions that lead to their issuers’ payment defaults and insolvency proceedings. In particular, distressed or defaulted obligations might be repaid, if at all, only after lengthy workout or bankruptcy proceedings during which the issuer might not make any interest or other payments, and the Fund may incur additional expenses in its effort to be repaid. If GMO’s assessment of the eventual recovery value of a distressed or defaulted debt investment proves incorrect, the Fund may lose a substantial portion or all of its original investment or may be required to accept cash or instruments worth less than its original investment.

Risk Return Abstract

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Risk [Text Block]

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●Market Risk – Asset-Backed Securities – The market price of asset-backed securities, like that of other fixed income investments, can decline for a variety of reasons, including increases in interest rates. In addition, the market price can decrease due to a reduction in or decrease in the reliability of their payment streams. Payment streams associated with asset-backed securities held by the Fund depend on many factors (e.g., the cash flow generated by the assets backing the securities, deal structure, and creditworthiness of any credit-support provider), and a problem in any of these factors can lead to a reduction in the payment stream GMO expected the Fund to receive when the Fund purchased the asset-backed security. The liquidity of asset-backed securities (particularly below investment grade asset-backed securities) may change over time. During periods of deteriorating economic conditions, such as recessions, or periods of rising unemployment, delinquencies and losses generally increase, sometimes dramatically, for asset-backed securities whose underlying assets consist of loans, sales contracts, receivables and other obligations.

Risk Return Abstract

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Risk [Text Block]

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●Derivatives and Short Sales Risk – The use of derivatives involves the risk that their value may not change as expected relative to changes in the value of the underlying assets, pools of assets, rates, currencies or indices. Derivatives also present other risks, including market risk, illiquidity risk, currency risk, credit risk, leveraging risk, commodities risk and counterparty risk. The market price of an option is affected by many factors, including changes in the market prices or dividend rates of underlying securities (or in the case of indices, the securities in such indices); the time remaining before expiration; changes in interest rates or exchange rates; and changes in the actual or perceived volatility of the relevant index or underlying securities. The Fund typically creates short investment exposure by selling securities short or by taking a derivative position in which the value of the derivative moves in the opposite direction from the price of an underlying asset, pool of assets, rate, currency or index. Specifically, the net asset value of the Fund’s shares will be adversely affected if the equities or other assets that are the subject of the Fund’s short exposures appreciate in value. The risk of loss associated with derivatives that provide short investment exposure and short sales of securities is theoretically unlimited.

Risk Return Abstract

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Risk [Text Block]

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●Non-U.S. Investment Risk – The market prices of many non-U.S. securities fluctuate more than those of U.S. securities. Many non-U.S. securities markets are less stable, smaller, less liquid, and less regulated than U.S. securities markets, and the cost of trading in those markets often is higher than in U.S. securities markets. In addition, non-U.S. securities issuers often are not subject to as much regulation as U.S. issuers, and the reporting, recordkeeping, accounting, custody, and auditing standards to which those issuers are subject often are not as rigorous as U.S. standards. In addition, the Fund is subject to taxation by countries other than the United States, including potentially on a retroactive basis, on (i) capital gains it realizes or dividends, interest, or other amounts it realizes or accrues in respect of non-U.S. investments; (ii) transactions in those investments; and (iii) repatriation of proceeds generated from the sale or other disposition of those investments. Also, the Fund needs a license to invest directly in securities traded in many non-U.S. securities markets, and the Fund is subject to the risk that its license is terminated or suspended. In some non-U.S. securities markets, prevailing custody and trade settlement practices (e.g., the requirement to pay for securities prior to receipt) expose the Fund to credit and other risks. Further, adverse changes in investment regulations, capital requirements or exchange controls could adversely affect the value of the Fund’s investments. The risks above (such as substantial price fluctuations and market instability, illiquidity and lack of regulation) and other risks (e.g., nationalization, expropriation or other confiscation of assets of non-U.S. issuers, difficulties enforcing legal judgments or contractual rights and geopolitical risks) tend to be higher for investments in the securities of issuers tied economically to emerging countries. The economies of emerging countries often depend predominantly on only a few industries or commodities and often are more volatile than the economies of developed countries.

Risk Return Abstract

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●Large Shareholder Risk – To the extent that a large number of shares of the Fund is held by a single shareholder (e.g., an institutional investor or another GMO Fund) or a group of shareholders with a common investment strategy (e.g., GMO asset allocation accounts), the Fund is subject to the risk that a redemption by that shareholder or group will require the Fund to sell investments at disadvantageous prices, disrupt the Fund’s operations, or force the Fund’s liquidation.

Risk Return Abstract

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Risk [Text Block]

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●Focused Investment Risk – Investments in countries, regions, asset classes, sectors, industries, currencies, or issuers that are subject to the same or similar risk factors and investments whose market prices are closely correlated are subject to higher overall risk than investments that are more diversified or whose market prices are not as closely correlated.

Risk Return Abstract

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Risk [Text Block]

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●Leveraging Risk – The use of derivatives, short sales and (if applicable) securities lending can create leverage. Leverage increases the Fund’s losses when the value of its investments (including derivatives) declines. In addition, the Fund’s portfolio will be leveraged if it exercises its right to delay payment on a redemption and the value of the Fund’s assets declines between the time a redemption request is treated as being received by the Fund and the time the Fund liquidates assets to fund that redemption.

Risk Return Abstract

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Risk [Text Block]

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●Futures Contracts Risk – The loss to the Fund resulting from its use of futures contracts is potentially unlimited. Futures markets are highly volatile, and the use of futures contracts increases the volatility of the Fund’s net asset value. A liquid secondary market may not exist for any particular futures contract at any particular time, and the Fund may be unable when it wishes to terminate its exposure under that contract. When the Fund uses futures contracts for hedging purposes, it runs the risk that changes in the prices of the contracts will not correlate perfectly with changes in the securities, index, or other asset underlying the contracts or movements in the prices of the Fund’s investments that are subject to the hedge. In addition, the Fund may be unable to recover or may be delayed in recovering margin or other amounts deposited with a futures commission merchant or futures clearinghouse. Foreign futures contracts are often less liquid and more volatile than U.S. futures contracts.

Risk Return Abstract

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